JMJ Diamond Tools provides high quality products to meet our customers needs. We could also help you to find and even design your products to achieve your goals by quality, quantity and services. Thank you for your business and let us win together! ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 8-inch Professional Diamond Core Bit for Fast Drilling Concrete and Asphalt in Both Wet and Dry Professional Quality Diamond Core Bit to Drill Concrete and Asphalt Fast Drilling Both Wet and Dry 17" long 1 1/4"-7 Thread Segment Height: 0.400"